Active built-to-order servo, ordered by code
The Siemens 1FK2104-4AF10-2MB0 is a SIMOTICS S-1FK2 HD servo motor in the 1FK2 compact high-dynamic family, shipped under product group 9021 / group code R220 and listed as product class C — built per order, not returnable against credit. Lifecycle reads as current on the Siemens record, so it is still being built rather than sourced as a discontinued spare. What actually decides the fit on the BOM line is the headline torque/speed pair: 1.27 Nm stall (M0) with 0.4 kW at nN = 3000 rpm on a 380–480 V supply, and a derated 0.2 kW at nN = 1500 rpm on 200–240 V. The 22-bit + 12-bit multiturn absolute encoder (AM22DQC) talks DRIVE-CLiQ straight into a SINAMICS S120 drive — that is the path the integrator will terminate, and it removes the need for a separate encoder cable run.
Holding brake, IP64, and what the shaft tells the panel builder
An integrated holding brake is part of the order code — for a vertical axis it is the safety element that holds load at standstill after the drive is powered off, so the BOM should not specify a separate brake. The shaft is a plain cylindrical D14 x 30 mm stub, which mates to a servo coupling or gear reducer selected by the machine builder; there is no keyway or feather in this code. IP64 on the motor body is a sealed enclosure rating — splash- and dust-tight for a cabinet-internal or light-outdoor machine envelope, not a washdown-duty figure. Power and feedback leave through M17 connectors; both are keyed, so the DRIVE-CLiQ signal lead and the power lead cannot be cross-mated at the field end.
Compliance, packaging, and what ships in the box
The motor is individually packed — 452 x 250 x 267 mm carton, one piece per package — and is not subject to dual-use export control (AL: N / ECCN: N), which simplifies cross-border shipments against a purchase order.
Procurement posture for 1FK2104-4AF10-2MB0
Because the part is built to order under product class C, the realistic buying path is to specify the order code against the BOM and request a quote — independent distributors price and confirm availability per RFQ, and the listing here is the same motor code Siemens would ship from the factory line. For a maintenance spare on a SINAMICS-driven axis, ordering the exact code keeps the encoder resolution, brake rating, and shaft geometry matched to the existing machine without a parameter re-load.